Lock mechanism for automatic guns



Ndv. 9, 1937. A. J. LAHTI LOCK MECHANISM FOL} AUTOMATIC GUNS Filveti July 6, 1936 fi jLa//7Z 7/ Patented Nov. 9, 1937 UNiTD STES ATE? OFFIQE Application July 6, 1936, Serial No. 89,209 In Germany September 23, 1935 1 Claim.

The present invention relates to lock mechanism of automatic guns the automatic function of which depends on the pressure of the powder gases as in the so-called gas guns, or on the short recoil of the barrel as in the so-called recoil guns.

The invention is fundamentally characterized by the fact that the connection between the lock and the barrel is effected by means of a type of one-armed locking lever, aided by the inclined plane provided on the closing piece, and that the connection is opened by a double armed lever which receives its movement from the backwardly sliding closing piece.

The above mentioned locking device, viz, the closing piece and the double armed lever, is capable of simple and mobile manufacture on account of its advantageous operation in the movement of a one armed lever and a double armed lever. These conditions are important factors in the guns mentioned, and particularly in obtaining a high rate of firing.

Reference will now be made to the accompanying drawing which shows the lock mechanism according to the invention adapted for use in a gas gun and in which;-

Figure 1 is a longitudinal section of the middle part of the gun and Figure 2 is a cross section on the line A-B of Fig. 1.

A lock mechanism is provided in the lock body I on the butt end of the gun, the main parts of which are a lock 2, a closing piece 3, a locking lever 4, a double armed lever 5, a striking pin 6 and a recoil spring 1. The barrel 8 and the gas cylinder 9 into which the powder gas is supplied in the known manner from the front part of the barrel, are screwed on to the front part of the casing I. The piston rod l!) which is constructed in the known manner and moves in the cylinder 9 is screwed on to the front part of the closing piece 3.

The operation of the lock arrangement is as follows;

When the gas arising from the shot passes into the cylinder 9 the piston with the piston rod H3 forces back the closing part 3, the striking surface 3a hitting the lower part of the shaft 5a of the double-armed lever '5. The double-armed lever 5 rotates about the pin H fixed in the lock and forces downwards the rear part of the locking lever 4 with its upper arm 51) in the out out portion 411 in the locking lever 4. The locking lever 4 rotates about a pin i2 supported on the lock 2 in such a way that the projection 4b therein is pressed into the 'cut out portion 35b of the closing part 3, the locking point do of the locking lever 4 drops to the rear side of a counter-part l3 fixed on the casing I, and connection between the lock 2 and the barrel 8 is opened.

The backward sliding movement of the closing part 3 continues on account of the pressure of the explosion and the lock 2 slides back with it, whilst the striking surface 3a moves by means of the lever 5a until the empty case is ejected in the known manner and lock 2 is in its rear position.

If firing is interrupted, the closing part 3 is held ready cooked with the tooth to on the discharge device, until loaded by hand, whereby the closing part 3 is drawn from the forward into the rear position with the help of a cooking bar of the known type, and the other parts of the locking device follow and operate in the above described manner.

If firing is maintained, and also if the cooking position is no longer maintained the spring 1 moves the closing part 3 forward. The inclined surfaces 3d of the closing part 3 are pressed against the rear edges of the projections 4b and the lock is moved forward and a new cartridge moves into the barrel 8 in the known manner from the cartridge chamber. When the lock 2 stops, the closing part 3 continues its forward movement and the inclined surface 3d moves the rear end of the locking lever 4 upwards, so that the locking point to is pressed against the counter-part 13 whilst it effects the connection between the lock 2 and the barrel 8. If the closing part 3 moves further forward its upper surface 30, whilst sliding against the projection 41), carries the locking parts 5 and prevents the same moving.

At the end of the forward movement the closing part 3 between the projection 3,1 and the fork 30 hits the striking pin 5 against the detonating cap and fires the cartridge, after which the recoil movement of the closing part 3 starts anew and the operation of the gun as described above continues.

With short recoil guns the operation is the same with the difference that the closing part 3 receives its movement from the recoiling barrel in the already known manner.

I claim:

In a recoil loading firearm the combination of a reciprocating breech block, a pivoted locking member on said block having an abutment seating in a recess of the breech to lock said breech block thereto, a double armed lever pivoted to said breech block having one arm cooperating with said locking member to release said member from said recess in said breech, an actuator 00- operating with the other arm of said lever to actuate the same and said actuator having a cam surface cooperating with said locking member to replace said member in said recess after having been removed therefrom by said lever.

AIMO' J OHANNES LAHTI. 

